The explosions put the city on edge and highlighted the terrorist threat that Russia is facing as it prepares to host the Winter Games in February.
UPDATED 5:00 AM -- Russia's main investigative agency says a Volgograd bus explosion was caused by a suicide bomber and officials raised the death toll to 14.
The bombing comes a day after 17 people died in a railway station bombing also blamed on a suicide bomber.
Investigative Committee spokesman Vladimir Markin said in a statement that Monday's explosion on an electric bus involved a similar bomb, proving a link between the two attacks.
Public health officials said that at least 14 people were killed in explosion during morning rush hour.
No one has claimed responsibility for either bombing, but they came a few months after Chechen rebel leader Doku Umarov threatened new attacks against civilian targets in Russia, including Olympics in Sochi in February.
MOSCOW (AP) -- Russia's Emergency Situations Ministry says at least 10 people have been killed in a bus explosion in Volgograd, a day after a suicide bombing that killed at least 17 at a railway station in the city.
The explosions put the city on edge and highlighted the terrorist threat that Russia is facing as it prepares to host the Winter Games in February. Volgograd is about 650 kilometers (400 miles) northeast of Sochi, where the Olympics are to be held.
There was no immediate claim of responsibility for either explosion, which came several months after Chechen rebel leader Doku Umarov called for new attacks against civilian targets in Russia, including the Sochi Games.
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